IEC/IEEE 60079-30-2:2015

Explosive atmospheres - Part 30-2: Electrical resistance trace heating - Application guide for design, installation and maintenance

IEC/IEEE 60079-30-2:2015 provides guidance for the application of electrical resistance trace heating systems in areas where explosive atmospheres may be present, with the exclusion of those classified as requiring EPL Ga/Da (traditional relationship to Zone 0 and Zone 20 respectively). This standard also provides guidance for explosive atmospheres incorporating the Division method of area classification that may be applied by some users of this standard. It provides recommendations for the design, installation, maintenance and repair of trace heating systems including associated control and monitoring equipment. It does not cover devices that operate by induction heating, skin effect heating or direct pipeline heating, nor those intended for stress relieving. This first edition of IEC/IEEE 60079-30-2 cancels and replaces the first edition of IEC 60079-30-2 published in 2007 and constitutes a technical revision. This edition includes the following significant changes, apart from a general review and updating of the first edition of IEC 60079-30-2, harmonization with IEEE Std.515, with respect to the previous edition:
- the relocation of trace heater product design methodology and requirements to IEC/IEEE 60079-30-1;
- the relocation and/or duplication of information on installation, maintenance, and repair to the MTs under SC31J for their addition into IEC 60079-14, IEC 60079-17, and IEC 60079-19;
- the inclusion of more detailed information on safety showers and eyewash units;
- the introduction of Annexes from IEEE Std. 515. Please refer to the Foreword of the document for the significance of changes between IEC 60079-30-2, Edition 1.0 (2007) and IEC/IEEE 60079-30-2, Edition 1.0 (2014). Keywords: electrical resistance trace heating systems, Division method of area classification

Atmosphères explosives - Partie 30-2: Traçage par résistance électrique - Guide d'application pour la conception, l'installation et la maintenance.

IEC/IEEE 60079-30-2:2015 fournit des lignes directrices pour l'application des systèmes de traçage par résistance électrique dans les emplacements où des atmosphères explosives peuvent être présentes, à l’exception de ceux classés comme exigeant l'EPL Ga/Da (relation traditionnelle à la Zone 0 et la Zone 20, respectivement). La présente norme donne également des lignes directrices relatives aux atmosphères explosives intégrant la méthode de classement des emplacements par division qui peut être appliquée par certains utilisateurs de la présente norme. Elle fournit des recommandations pour la conception, l'installation, la maintenance et la réparation des systèmes de traçage, y compris le matériel associé de commande et de surveillance. Elle ne couvre pas les dispositifs qui fonctionnent par chauffage par induction, chauffage à effet de peau ou chauffage par impédance, ni ceux destinés au relâchement des contraintes. Cette première édition de l'IEC/IEEE 60079-30-2 annule et remplace la première édition de l'IEC 60079-30-2 parue en 2007. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes, hormis la révision générale et la mise à jour de la première édition de l'IEC 60079-30-2 et de l'harmonisation avec la norme IEEE 515, par rapport à l'édition précédente:
- déplacement de la méthode de conception des résistances de traçage et des exigences dans l'IEC/IEEE 60079-30-1;
- déplacement et/ou reproduction des informations relatives à l'installation, la maintenance et la réparation à l’intention des équipes de maintenance (MT) relevant du SC31J, dans l'IEC 60079-14, l'IEC 60079-17 et l'IEC 60079-19;
- introduction d'informations plus détaillées relatives aux douches de sécurité et aux bassins oculaires;
- introduction des Annexes issues de la norme IEEE 515.
Référence à l'avant-propos du document concernant l'importance des modifications entre la CEI 60079-30-2, édition 1.0 (2007) et la CEI / IEEE 60079-30-2, édition 1.0 (2014)

General Information

• Status: Published
• Publication Date: 27-Sep-2015
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: TC 31 - Equipment for explosive atmospheres
• Drafting Committee: MT 60079-30 - TC 31/MT 60079-30
• Current Stage: PPUB - Publication issued
• Start Date: 15-Jul-2015
• Completion Date: 28-Sep-2015

Relations

• Replaces: IEC 60079-30-2:2007 - Explosive atmospheres - Part 30-2: Electrical resistance trace heating - Application guide for design, installation and maintenance
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/IEEE 60079-30-2 ®
Edition 1.0 2015-09
INTERNATIONAL
STANDARD
colour
inside
Explosive atmospheres –
Part 30-2: Electrical resistance trace heating – Application guide for design,
installation and maintenance
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing being
secured. Requests for permission to reproduce should be addressed to either IEC at the address below or IEC’s

member National Committee in the country of the requester or from IEEE.

IEC Central Office Institute of Electrical and Electronics Engineers, Inc.
3, rue de Varembé 3 Park Avenue
CH-1211 Geneva 20 New York, NY 10016-5997
Switzerland United States of America
Tel.: [phone] [e-mail]
Fax: [phone] www.ieee.org
[e-mail]
www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About the IEEE
IEEE is the world’s largest professional association dedicated to advancing technological innovation and excellence for
the benefit of humanity. IEEE and its members inspire a global community through its highly cited publications,
conferences, technology standards, and professional and educational activities.

About IEC/IEEE publications
The technical content of IEC/IEEE publications is kept under constant review by the IEC and IEEE. Please make sure
that you have the latest edition, a corrigendum or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in
documents. Available for PC, Mac OS, Android Tablets 15 additional languages. Also known as the International
and iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 60 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and
committee,…). It also gives information on projects, Definitions clause of IEC publications issued since 2002.
replaced and withdrawn publications. Some entries have been collected from earlier publications

of IEC TC 37, 77, 86 and CISPR.
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details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer
Service Centre: [e-mail].
IEC/IEEE 60079-30-2 ®
Edition 1.0 2015-09
INTERNATIONAL
STANDARD
colour
inside
Explosive atmospheres –
Part 30-2: Electrical resistance trace heating – Application guide for design,

installation and maintenance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.260.20 ISBN 978-2-8322-2736-7

– 2 – IEC/IEEE 60079-30-2:2015
© IEC/IEEE 2015
CONTENTS
FOREWORD . 6
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 10
4 Application considerations . 10
4.1 General . 10
4.2 Corrosive areas . 11
4.3 Process temperature accuracy . 11
4.3.1 Type I . 11
4.3.2 Type II . 11
4.3.3 Type III . 11
4.4 Installation considerations . 11
5 Thermal insulation . 12
5.1 General . 12
5.2 Selection of insulating material . 12
5.3 Selection of weather barrier (cladding) . 13
5.4 Selection of economical thickness to provide optimum trace heating design. 13
5.5 Double insulation . 14
6 System design . 17
6.1 General . 17
6.2 Purpose of, and major requirement for, trace heating . 17
6.3 Training . 18
6.4 Selection of trace heater . 18
6.4.1 General . 18
6.4.2 Site-fabricated trace heaters . 18
6.4.3 Specific types of trace heating . 19
6.5 Maximum temperature determination . 19
6.5.1 General . 19
6.5.2 PTC characteristic . 19
6.5.3 Stabilized design . 20
6.5.4 Controlled design. 20
6.6 Heat up and cool down considerations . 20
6.7 Design information . 20
6.7.1 Design information documentation . 20
6.7.2 Isometric or trace heater configuration line lists and load charts . 21
6.8 Power system . 22
6.9 Earthing requirements . 22
6.10 Earth-fault protection of equipment . 23
6.11 Start-up at minimum ambient temperatures . 23
6.12 Long trace heater runs . 23
6.13 Flow pattern analysis . 23
6.14 Dead-leg control technique . 25
6.15 Chimney effect . 25
6.16 Safety shower and eyewash station design requirements . 26

© IEC/IEEE 2015
7 Control and monitoring . 26
7.1 General . 26
7.2 Mechanical controllers . 27
7.3 Electronic controllers . 27
7.4 Application suitability . 27
7.5 Location of controllers . 27
7.6 Location of sensors . 28
7.7 Alarm considerations . 28
7.7.1 General . 28
7.7.2 Trace heating circuit alarm . 28
7.7.3 Temperature alarms . 29
7.7.4 Other alarms . 29
7.7.5 Integrated control . 29
8 Recommendations for installation . 29
8.1 General . 29
8.2 Preparatory work . 30
8.2.1 General . 30
8.2.2 Scheduling and coordination . 30
8.2.3 Confirmation of equipment . 30
8.2.4 Receiving materials . 30
8.2.5 Warehousing and handling . 30
8.2.6 Personnel aspects . 30
8.3 Installation of trace heating circuits . 30
8.3.1 Coordination and equipment verification . 30
8.3.2 Pre-installation testing and design verification . 31
8.3.3 Visual examination . 31
8.3.4 Insulation resistance test . 31
8.3.5 Component substitution . 31
8.3.6 Location of power supply . 31
8.3.7 Installation of trace heaters . 32
8.3.8 Connections and terminations . 34
8.4 Installation of control and monitoring equipment . 36
8.4.1 General . 36
8.4.2 Verification of equipment suitability. 36
8.4.3 Temperature controller and monitoring devices . 36
8.4.4 Sensor considerations . 36
8.4.5 Controller operation, calibration, and access . 40
8.4.6 Necessary modifications . 40
8.5 Installation of thermal insulation system (see also Clause 5) . 40
8.5.1 General . 40
8.5.2 Preparatory work . 40
8.5.3 Installation of the thermal insulation materials . 40
8.5.4 Cladding . 41
8.5.5 Field (site work) circuit insulation resistance test . 41
8.5.6 Visual inspection . 41
8.5.7 Documentation .
...

IEC/IEEE 60079-30-2 ®
Edition 1.0 2015-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Explosive atmospheres –
Part 30-2: Electrical resistance trace heating – Application guide for design,
installation and maintenance
Atmosphères explosives –
Partie 30-2: Traçage par résistance électrique – Guide d'application pour la
conception, l'installation et la maintenance

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing being
secured. Requests for permission to reproduce should be addressed to either IEC at the address below or IEC’s
member National Committee in the country of the requester or from IEEE.

IEC Central Office Institute of Electrical and Electronics Engineers, Inc.
3, rue de Varembé 3 Park Avenue
CH-1211 Geneva 20 New York, NY 10016-5997
Switzerland United States of America
Tel.: [phone] [e-mail]
Fax: [phone] www.ieee.org
[e-mail]
www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About the IEEE
IEEE is the world’s largest professional association dedicated to advancing technological innovation and excellence for
the benefit of humanity. IEEE and its members inspire a global community through its highly cited publications,
conferences, technology standards, and professional and educational activities.

About IEC/IEEE publications
The technical content of IEC/IEEE publications is kept under constant review by the IEC and IEEE. Please make sure
that you have the latest edition, a corrigendum or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing 20 000 terms and definitions in
Technical Specifications, Technical Reports and other English and French, with equivalent terms in 16 additional
documents. Available for PC, Mac OS, Android Tablets languages. Also known as the International
and iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a 65 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
committee,…). It also gives information on projects, IEC publications issued since 2002. Some entries have
replaced and withdrawn publications. been collected from earlier publications of IEC TC 37, 77,

86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished

Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer
Service Centre: [e-mail].
IEC/IEEE 60079-30-2 ®
Edition 1.0 2015-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Explosive atmospheres –
Part 30-2: Electrical resistance trace heating – Application guide for design,

installation and maintenance
Atmosphères explosives –
Partie 30-2: Traçage par résistance électrique – Guide d'application pour la

conception, l'installation et la maintenance

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.260.20 ISBN 978-2-8322-5200-0

– 2 – IEC/IEEE 60079-30-2:2015
© IEC/IEEE 2015
CONTENTS
FOREWORD . 6
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 10
4 Application considerations . 10
4.1 General . 10
4.2 Corrosive areas . 11
4.3 Process temperature accuracy . 11
4.3.1 Type I . 11
4.3.2 Type II . 11
4.3.3 Type III . 11
4.4 Installation considerations . 11
5 Thermal insulation . 12
5.1 General . 12
5.2 Selection of insulating material . 12
5.3 Selection of weather barrier (cladding) . 13
5.4 Selection of economical thickness to provide optimum trace heating design. 13
5.5 Double insulation . 14
6 System design . 17
6.1 General . 17
6.2 Purpose of, and major requirement for, trace heating . 17
6.3 Training . 18
6.4 Selection of trace heater . 18
6.4.1 General . 18
6.4.2 Site-fabricated trace heaters . 18
6.4.3 Specific types of trace heating . 19
6.5 Maximum temperature determination . 19
6.5.1 General . 19
6.5.2 PTC characteristic . 19
6.5.3 Stabilized design . 20
6.5.4 Controlled design. 20
6.6 Heat up and cool down considerations . 20
6.7 Design information . 20
6.7.1 Design information documentation . 20
6.7.2 Isometric or trace heater configuration line lists and load charts . 21
6.8 Power system . 22
6.9 Earthing requirements . 22
6.10 Earth-fault protection of equipment . 23
6.11 Start-up at minimum ambient temperatures . 23
6.12 Long trace heater runs . 23
6.13 Flow pattern analysis . 23
6.14 Dead-leg control technique . 25
6.15 Chimney effect . 25
6.16 Safety shower and eyewash station design requirements . 26

© IEC/IEEE 2015
7 Control and monitoring . 26
7.1 General . 26
7.2 Mechanical controllers . 27
7.3 Electronic controllers . 27
7.4 Application suitability . 27
7.5 Location of controllers . 27
7.6 Location of sensors . 28
7.7 Alarm considerations . 28
7.7.1 General . 28
7.7.2 Trace heating circuit alarm . 28
7.7.3 Temperature alarms . 29
7.7.4 Other alarms . 29
7.7.5 Integrated control . 29
8 Recommendations for installation . 29
8.1 General . 29
8.2 Preparatory work . 30
8.2.1 General . 30
8.2.2 Scheduling and coordination . 30
8.2.3 Confirmation of equipment . 30
8.2.4 Receiving materials . 30
8.2.5 Warehousing and handling . 30
8.2.6 Personnel aspects . 30
8.3 Installation of trace heating circuits . 30
8.3.1 Coordination and equipment verification . 30
8.3.2 Pre-installation testing and design verification . 31
8.3.3 Visual examination . 31
8.3.4 Insulation resistance test . 31
8.3.5 Component substitution . 31
8.3.6 Location of power supply . 31
8.3.7 Installation of trace heaters . 32
8.3.8 Connections and terminations . 34
8.4 Installation of control and monitoring equipment . 36
8.4.1 General . 36
8.4.2 Verification of equipment suitability. 36
8.4.3 Temperature controller and monitoring devices . 36
8.4.4 Sensor considerations . 36
8.4.5 Controller operation, calibration, and access . 40
8.4.6 Necessary modifications . 40
8.5 Installation of thermal insulation system (see also Clause 5) . 40
8.5.1 General . 40
8.5.2 Preparatory work .
...